clay

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You need to replicate a small part on a 3-D printer, so you start getting your tools together. Calipers, rulers, and a sketch pad at a minimum, and if you’re extra fancy, maybe you pull out a 3D-scanner to make the job really easy. But would you raid your kid’s stash of Play-Doh too?

You might, if you want to follow [Vladimir Mariano]’s lead and use Play-Doh for accurately modeling surface features in the part to be replicated. Play-Doh is a modeling compound that kids and obsolete kids alike love to play with, especially a nice fresh can before it gets all dried out or mixed in with other colors or gets dog hair stuck in it.

For [Vladimir], the soft, smooth stuff was the perfect solution to the problem of measuring the spacing of small divots in the surface of a cylinder that he was asked to replicate. Rather than measuring the features directly on the curved surface, he simply rolled it across a flattened wad of Play-Doh. The goop picked up the impressions on the divots, which were then easy to measure and transfer to Fusion 360. The video below shows the Play-Doh trick up front, but stay tuned through the whole thing to get some great tips on using the sheet metal tool to wrap and unwrap cylinders, as well as learning how to import images and recalibrate them in Fusion 360.

Building a one-off prototype is usually pretty straightforward. Find some perfboard and start soldering, weld up some scrap metal, or break out the 3D printer. But if you’re going to do a production run of a product then things need to have a little more polish. In [Eric Strebel]’s case this means saving on weight and material by converting a solid molded part into something that is hollow, with the help of some lasagna.

What [Eric] walks us through in this video is how to build a weep mold. First, the solid part is cast in silicone. Using the cast, some “sheet clay” is applied to the inside which will eventually form the void for the new part’s walls. The clay needs to be flush with the top of the mold, though, and a trick to accomplish this task is to freeze the mold (next to the lasagna) which allows the clay to be scraped without deforming.

From there, the second half of the mold is poured in, using special channels that allow the resin to “weep” out of the mold (hence the name). This two-part process creates a much more efficient part with thin walls, rather than the expensive solid prototype part.

Most of our 3D printers print in plastic. While metal printing exists, the setup for it is expensive and the less expensive it is, the less impressive the results are. But there are other materials available, including ceramic. You don’t see many hobby-level ceramic printers, but a company, StoneFlower, aims to change all that with a print head that fits a normal 3D printer and extrudes clay. You can see a video of the device, below. They say with some modifications, it can print other things, including solder paste.

The concept isn’t new. There are printers that can do this on the market. However, they still aren’t a common item. Partially, this is a cost issue as many of these printers are pricey. They also often require compressed air to move the viscous clay through tubes. StoneFlower has a syringe pump that doesn’t use compressed air.

Clay is a shapeless raw material that’s waiting to be turned into awesomeness by your creativity. So is the Raspberry Pi. [Dorison Hugo] brought the two together in his artfully crafted SNES micro – a tiny retro gaming console sculpted from clay.

[Massimo Moretti] has a big idea – to build housing on the cheap from locally sourced materials for a burgeoning world population. He also has a background in 3D printing, and he’s brought the two concepts together by building a 12 meter tall delta-bot that can print a house from clay.

The printer, dubbed Big Delta for obvious reasons, was unveiled in a sort of Burning Man festival last weekend in Massa Lombarda, Italy, near the headquarters of [Moretti]’s WASProject. From the Italian-language video after the break, we can see that Big Delta moves an extruder for locally sourced clay over a print area of about 20 square meters. A video that was previously posted on WASProject’s web site showed the printer in action with clay during the festival, but it appears to have been taken down by the copyright holder. Still, another video of a smaller version of Big Delta shows that clay can be extruded into durable structures, so scaling up to full-sized dwellings should be feasible with the 4 meter delta’s big brother.

Clay extrusion is not the only medium for 3D printed houses, so we’ll reserve judgment on Big Delta until we’ve seen it print a livable structure. If it does, the possibilities are endless – imagine adding another axis to the Big Delta by having it wheel itself around a site to print an entire village.

Artist [Jonathan] has built a 3D printer specifically for printing in clay. The part count is kept to a minimum and the printer was designed to be made with basic tools and beginner skills. The intent was to not require access to a plastic 3D printer in order to build this printer. Although this build’s goal was clay printing, the extruder could certainly be swapped out for a typical plastic printer version.

This Delta uses quite a bit of MDF. The top and bottom plates are MDF, as are the bearing carriages and extruder mount plate. 12mm rods are solely responsible for the support between the top and bottoms plates as well providing a surface for the LM12UU linear bearings. These bearings are zip tied to the MDF bearing carriages. The 6 arms that support the extruder mount plate are made from aluminum tubing and Traxxas RC car rod-ends. NEMA17 motors and GT2 belts and pulleys are the method used to move the machine around.

Getting the clay to dispense was a tricky task. Parts scavenged from a pneumatic dispensing gun was used. If you are unfamiliar with this type of tool, think: Power Caulk Gun. Clay is fed into the re-fillable syringes and an air compressor provides the 30 psi required to force the clay out of the nozzle. The pressure alone controls the rate of clay flow so it is a little finicky to get the extrusion rate correct. Depending on the size of the final sculpture, 1 to 2mm diameter nozzles could be used. For larger work, 1mm layer height works well. For the smaller pieces, 0.5mm is the preferred layer height.

The wheel goes round and round as does [Lou Wozniak]. He’s come back to us, this time hacking together a pottery wheel from a cheap ceiling fan. This is a great use for a discarded or inexpensive fan and the build should cost less than $50. As you watch the video you learn that repurposing the ceiling fan was no simple feat. Lucky for us [Lou] spins through detailed construction procedures and doesn’t fail to cover every tip and trick. He really does think outside the box or should we say inside the bucket and peanut butter jar. The fan gets dismantled as well as rewired inside a 5 gallon bucket which is used as the pottery wheel housing and stand. A plastic peanut butter jar was used as a makeshift electrical junction box inside the bucket. He remounted the motor’s string operated speed switch on the side of the jar and routed the pull string out the side of the bucket. The fan motor should have three or four switch speed settings which might be enough control. If continuous variable speed control is desired he could add in a controller similar to [Ben Krasnow’s] AC controller using one pin on a microcontroller. UPDATE: [AKA the A] tells us in a comment below that this controller won’t work with a ceiling fan, but we still really like [Ben’s] project so we’re leaving this link here.

Most potters use significant amounts of water to wet the clay while they throw, so we have reservations about having the high voltages and open motor design directly under the wheel with no shielding. We know [Lou] could easily hack in a splash pan and of course always plug into a ground fault protected receptacle when using electrical appliances around water.

We do get to see the wheel in operation at the end of the video, which you can watch after the break. However, [Lou] makes no claims at being a pottery artisan.